1. Field of the Invention
This invention relates to a mixer-washer apparatus and more particularly, to a powered mixer-washer apparatus that holds a mixing vessel mechanically, that attaches said mixing vessel to a mixer motor semi-automatically or automatically, that mixes a variety of materials with or without application of vacuum semi-automatically or automatically, and that washes said mixing vessel semi-automatically or automatically.
2. Description of the Prior Art
Power mixers are old and well known but have generally been of the type requiring manual washing or cleaning of a mixing vessel after the materials have been mixed in, and removed from, said mixing vessel. Such washing or cleaning is a tedious, time-consuming job and generally, it is difficult to clean all the surfaces thoroughly by hand. Moreover, it is extremely hazardous for one to wash or clean a mixing vessel that had been used to mix chemicals, drugs, radioactive materials, or other toxic compounds. Furthermore, many materials used in preparing models or molds, harden quickly after mixing, requiring one to pour the mixture into the mold or to form a mold as soon as possible, thereby not permitting time to wash or clean the mixing vessel before using the mixed materials. It is highly advantageous to have an automatic or semi-automatic mixer-washer to enable one to mix rapidly and to wash the mixing vessel while one is working with castings, molds or models.
Typical examples of mixing devices commonly used heretofore and at present are described in U.S. Pat. No. 1,847,227, mixing and agitating machine for drinks or food; U.S. Pat. No. 3,263,970, power mixer with motor started automatically when parts are assembled; U.S. Pat. No. 3,358 973, mixing apparatus for mixing asphalt, concrete and the like; U.S. Pat. No. 4,095,288, variable agitator mixer or washer. However, none of these patents describe mixing and washing as described in the present invention.
Patents that describe vacuum mixing devices include U.S. Pat. Nos. 2,453,914; 2,696,022; 2,777,177; 2,973,187; 3,139,270; 3,358,971; 3,557,411; 3,640,510. U.S. Pat. No. 3,640,510 describes a vacuum stirring device which has a time switch to determine the duration of mixing. However, none of the cited patents describe vacuum mixing and washing with the automatic or semi-automatic features described in the present invention. U.S. Pat. Nos. 2,696,022 and 2,777,177 describe an investment mixer in which a vacuum is established during the mixing and subsequent casting operation; however, no washing of the mixing vessel after completing the mixing and casting operations is claimed.